Mexican officials in the central state of Guanajuato say seven bodies have been found in the city of Salamanca and they appear to be members of a criminal organization.

The state attorney general's office says three of the victims were shot, and they have been identified.

Four others also were found Friday — dismembered in black plastic bags in two separate locations, on the side of a highway and in a neighborhood.

Written messages from a rival gang were found next to the bags. The agency spokesman declined to name the alleged criminal groups, but said they sell drugs and stolen gasoline.